Short Title: MEOP Project URL: http://biology.st-andrews.ac.uk/seaos/index.html Proposal URL: http://classic.ipy.org/development/eoi/proposal-details.php?id=153 Marine Mammal Exploration of the Oceans Pole to Pole (MEOP) will deploy state-of-the-art animal-borne CTD tags on strategically chosen, deep-diving marine mammal species to explore their movement patterns, behaviour and habitat utilization in Polar Regions. Concomitant with the ecological data regarding these top predators, a vast, high-precision oceanographic data set will be collected covering logistically difficult areas of ocean in Polar Seas at the fringes of the North and South Atlantic and the South Pacific that are strategically important to climate and ocean modelling. The cross-disciplinary merging of classical oceanography and marine mammal ecology will significantly advance our understanding of the world's oceans and top predators that live in them.

MEOP partners will deploy CTD-tags on beluga whales (Delphinapterus leucas), hooded seals (Cystophora cristata), Weddell seals (Leptonychotes weddellii), crabeater seals (Lobodon carcinophaga) and southern elephant seals (Mirounga leonina). Most of these species are very deep divers, with maximum dive depths that exceed 1000 m. Virtually all marine mammals forage in oceanic "hot-spots" where productivity is high, which also coincide with human fisheries efforts and areas of high oceanographic interest. Our target species inhabit areas with significant seasonal ice-cover in both the Arctic and the Antarctic, the edges of which are of particular interest to oceanographers in terms of deep-water formation. Ice-filled waters are rarely sampled by standard oceanographic studies using ships or other methodologies especially over extended times because of logistical and cost constraints, but they are routinely visited by these polar marine mammals. MEOPs oceanographic data will also ehance our ability to accurately model currents and deal with basin scale models.

This study is especially timely given the predictions for ecosystem changes in both Arctic and Antarctic systems within the coming decades due to climate change, in addition to increasing fisheries and tourism activities in both the Arctic and Antarctic.